1. Field of the Invention
The present disclosure relates to a needle plate replacement device that attaches and detaches a needle plate of a sewing machine to a bed portion of a machine frame and, in particular, relates to a needle plate replacement device with a lock, the needle plate replacement device with a lock being capable of preventing the mounted needle plate from being unexpectedly dislocated.
2. Description of the Related Art
A needle thread catching mechanism and a feeding mechanism, such as a lower shaft that synchronizes with the upper shaft that drives a needle and a hook that is interlocked with the lower shaft, are accommodated inside a bed portion of a sewing machine on which a needle plate is attached. When performing maintenance on the sewing machine, such as coping with troubles related to the above motion mechanisms, there are cases in which the needle plate needs to be detached and attached.
Furthermore, there are cases in which the needle plate is replaced with a needle plate for straight stitch or a needle plate for zigzag stitch in accordance with the purpose of the sewing.
Since the needle plate includes a needle hole through which a needle penetrates, when mounting the needle plate on the sewing machine, the needle hole needs to be accurately positioned at where the needle descends; accordingly, the needle plate needs to be attached while performing accurate positioning with respect to the machine frame of the sewing machine.
There is a needle plate attaching and detaching mechanism for coping with the above issue that has been hitherto known that facilitates attachment and detachment (see Japanese Unexamined Patent Application 2013-48846, for example). The needle plate attaching and detaching mechanism requires no tool such as a screwdriver, includes a releasing mechanism that enables the mounted needle plate to be easily dismounted, and in mounting the needle plate, allows positioning and fixing to be performed with a simple operation.